Characterization of beta-galactosidase from alternaria alternata on solid-state cultivation

The effects of orange peel, lemon peel, apple peel, wheat-bran and watermelon peel on beta-galactosidase production from Alternaria alterrtata were studied. Beta-galactosidase (EC-3.2. 1.23) was produced best by solid-state fermentation of A. alternata on wheat bran. The effects of pH and incubation temperature were studied. The highest enzyme activity was obtained at 50°C and pH 5.0. The enzyme was relatively stable in the pH range 3.0-5.0 and between 20°-50°C. The enzyme maintained 85% of its activity at 20°-30°C and 70% at 50°C. Activity was more than 92% between pH 3.0-5.0 and 42% in 40 mm and 50% in 30 mm at 60°C. In addition, glucose did not have an inhibitory effect.